Question

If a wrire of one ohm is sriked to doubles its lanth then resistance will be

Answer 1

R⁰= 1ohm , Rⁿ = ?? , l⁰ = l , lⁿ = 2l , A⁰ =A , Aⁿ = A/2

Rⁿ = ¶ 2l / A/2 =>Rⁿ = ¶4l /A ---(2)

R⁰ = ¶l⁰/A⁰ ---(1)

by (2) / (1) ,

Rⁿ /1 = (¶4l /A)/ (¶l/A) => Rⁿ = 4

•°• Rⁿ = 4 ohm